Blast furnace top structure

ABSTRACT

An improvement in a blast furnace top structure designed for facilitating the replacement of a part of said structure, which may be, for instance, divided into three stages, stages I, II and III. Floors support the stages I and II, respectively, said floors being elongated in the direction different from the crane running direction. Guide rails laid on the respective floors support wheels fitted on the stages I and II, respectively, so that the stages I and II can be moved aside on said rails, whereby the stage III can be easily replaced without need of moving the stages I and II down onto the ground.

United States Patent 1 Kishikawa et a].

[5 BLAST FURNACE TOP STRUCTURE [73] Assignee: Nippon Steel Corporation, Tokyo,

Japan 22 Filed: Dec, 20, 1971 211 Appl. No.: 209,556

[30] Foreign Application Priority Data Primary Examiner-Andrew R. J'uhasz Assistant Examiner-W. R. Briggs Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [5 7] ABSTRACT An improvement in a blast furnace top structure designed for facilitating the replacement of a part of said structure, which may be, for instance, divided into three stages, stages I, II and III. Floors support the stages I and II, respectively, said floors being elongated in the direction different from the crane running direction. Guide rails laid on the respective floors support wheels fitted on the stages I and II, respectively, so that the stages I and II can be moved aside on said rails, whereby the stage III can be easily replaced without need of moving the stages I and II down onto the ground.

3 Claims, 8 Drawing Figures Dec. 21, 1970 Japan 45-127688 [52] U.S. Cl. 266/31, 266/25 [51] Int. Cl C21b 7/18 [58] Field of Search 266/25, 31, 27; 214/36, A 214/35 [56] I References Cited FOREIGN PATENTS OR APPLICATIONS 231,84] 8/1959 Australia. 214/36 PATENTEDAPMSIBM 1 3 2 SHEEI 1 BF 5 FIG. I

L I2 m! INVENTOR-S Naoro Kishikowa Minoru Kosugi Youichl Iwamaru ATTORNESS mam 16 I974 3Q8-04l392 sum 2 or s INVENTORS Naoio Kishikawa Mlnoru Kosugi Youichl Iwamaru lO w .wflumbbl v ATTORNEY PATENTEIJAPR 15 1914 3304392 sum 2 1r 5 INVENTORS Naoro Klshikowa Minoru Kosugi Yaulch' Iwamoru BY Lwwpmzji ATTORNEY PATENTEDAPR 16 m4 3; 804.392

' SHEET 0F 5 INVENTORS N aoro Kishikawo Minoru Kosugi Youichi Iwamaru wumlwu amd ATTORNEYS 1 BLAST FURNACE TOP STRUCTURE The present invention relates to an improvement in a blast furnace top structure, more particularly an improvement designed to reduce the time required for the 5 replacement of the large bell and the large bell cup of the furnace top structure without the necessity of taking down other parts of the furnace top structure to the ground, and a method for replacing the large bell and large bell cup by means of said improvement.

In recent years, with the tendencies for blast furnaces to become increasingly large in size and using a still higher pressure, the conditions of use of a blast furnace top apparatus, particularly use of the large bell and large bell cup became so severe that the life of the furl5 nace top apparatus has been greatly shortened and the necessity of replacing the large bell and large bell cup by new ones has increased.

Heretofore, however, the work involved in removing various parts of the blast furnace top structure, which 20 was a prerequisite for replacing the large bell and large bell cup, was difficult and troublesome on account of their arrangement, working environment and heavy weight, and the suspension of the furnace operation for a long time was often necessitated during the replace- 25 ment of the large bell and'large bell cup, which necessarily brought about a reduction of production and a large loss thereby. Therefore, it has become important to solve the problem of how to extend the life of the furnace topstructure, that is, to reduce the frequency of the replacement of the large bell and large bell cup and to shorten the time required for the replacement.

The conventional way of replacing the large bell and large bell cup, and the improvement in the furnacetop structure according to the present invention which makes possible an easier. way of replacement will be explained with reference to the attached drawings, in which FIG. 1 is a schematic vertically sectioned view of a conventional blast furnace top structure.

FIG. 2 is a plan view of the structure of FIG. 1.

FIG. 3 is a schematic vertically sectioned view of a blast furnace top structure according to the present invention. I 45 FIG. 4 is a sectional view taken on line A-A in FIG.

FIG. 5 is a sectional view taken on line B-B in FIG. 3.

FIG. 6 is a sectional view taken on line C--C in FIG. 3.

FIG. 7a is an explanatory view showing the steps in the replacement of a large bell cup in the conventional blast furnace top structure.

FIG. 7b is an explanatory view showing the steps in the replacement of a large bell cup in the blast furnace top structure according to the present invention.

In the more modern furnace top apparatus, there is usually used atriple seal construction, which is composed of a large hell I, a large bell cup 2, a small bell 3 and a small bell cup 4 and in addition thereto a sealing valve 5, as shown in FIG. 1. This is to improve the air-tighteness with respect to the furnace top pressure of the blast furnace and to prevent the large bell l and the large bell cup 2, which are most difficult to replace, from being worn by a dust-containing high pressure gas current within the furnace. On the other hand, however. the furnace top structure is made more complicated by the above construction, so that the replacement of the large bell 1 and large bell cup 2 has become very difficult.

In a conventional way of replacing the large bell and large bell cup the replacement work is carried out by first dividing the furnace top structure into several stages: for instance, in the structure as shown in FIGS. 1 and 2 the furnace top structure is divided into three stages, that is, stages I, II and III. The stage I is composed of a rotary chute and a hopper, the stage II is composed of a small bell, a small bell cup and a hopper and the stage III is composed of a large bell and a large bell cup. Usually, when replacing the large bell and large bell cup, which belong to the: stage III, stages I and II must first be removed temporarily.

In the practical way of replacing the large bell 1 and large bell cup 2, at first they are temporarily connected with each other by fixing members 6, and a large bell rod 7 and a small bell rod 8, by which the large bell l and the small bell 3 are suspended from above respectively, are pulled upwards to a height higher than a crane girder 9.

Thereafter, the stages I and II are removed and brought down onto the ground or onto an operating floor around the furnace by means of a crane 10 which runs on the crane girder 9. Subsequently, in the same manner the stage III is removed and brought down onto a waiting place 13 on the ground. Then a newly made large bell and large bell cup are hoisted up and placed in the original position of the furnace top in a manner opposite to the above-mentioned manner, and thereafter the stages I and II are hoisted up from the ground or the casting floor 11 to the furnace top, and then the large bell rod 7 and the small bell rod 8 are connected to the large bell and the small bell respectively to complete the replacement operation. These procedures are shown in FIG. 7a.

Thus, the conventional manner of replacing the large bell and large bell cup has various disadvantages, Because not only the large bell and large bell cup, which are to be replaced, but also the stages I and II, which are working in good order and need not to be replaced, must be removed and brought down onto the ground or the operating floor by means of the furnace top crane 10, too much time is required for the replacing work and moreover an overhead crane having a large capacity and a large storage area, to which the stages I and II must be moved and in which they must wait for the completion of the replacement of the stage I, must be provided on the operating floor. Further, the replacement operation is dangerous in its nature on account of the steps which must be carried out in a high place. Therefore, the present invention seeks to eliminate these disadvantages and to provide an improvement in a furnace top structure, by means of which the replacement of the large bell and large bell cup can be carried out easily and within a short time.

The present invention provides an improved a blast furnace top structure which is divided into, for instance, three stages, stages I, II and III, said stage I being composed of a chute and hopper, the stage II being composed of a small bell, a small bell cup and a 5 hopper and the stage III being composed of alarge bell and a large bell cup. Supporting floors are provided for supporting the stage I and stage II, respectively, said supporting floors being elongated in a direction different from the direction in which the crane runs and guide rails are provided on the respective supporting floors. Wheels are mounted on the hopper of stage I on a bracket and wheels are mounted on an upper mantle of the stage II on a bracket, and the wheels run on said rails so that the stages I and II can be moved aside on the respective guide rails to provide sufficient space to permit replacement of stage III.

An embodiment of the structure of the present invention will be described with reference to the FIGS. 3 to 6.

In this specification the description is of the case in which the furnace top structure is divided into three stages as described above. The present invention is, however, not limited to this case. A different furnace top structure can be divided otherwise. For instance, the structure may be divided into two stages. In this case, the stage I is composed of a chute, a hopper, a small bell and small bell cup and the stage II is composed of a large bell and a large bell cup. There can also be a case in which the structure may be divided into three stages I, II and III, but the stage I is composed of two hoppers and the stage II is composed of a small bell, a small bell cup, a hopper and a chute.

The present invention may also be, of course, applied also to these cases without any difficulty.

The stage I is composed of a chute I4 and a hopper l5. Axles I8 are mounted on the outside of the hopper 15 on brackets and wheels 19 are rotatably mounted on said axles 18. The rails 20, on which the wheels 19 run, are laid on the floor 16 supporting the stage I, said floor being elongated by 3-5 meters beyond the original floor in a direction at right angles to (in this embodiment) or in the opposite direction to that in which a crane girder 9 extends. Therefore, the stage is so arranged that it is mounted on the rails 20 through the axles l8 and the wheels 19 and can be moved horizontally n the rails to a waiting place provided on the elongated floor 16, where the stage I waits until the replacement of the stage III is finished. Further, a fixing device can be provided between the stage and the floor 16 so that during the operation of the blast furnace the stage can be fixed to the floor.

A plurality of axles 22, preferably four, are mounted on the outside of the upper mantle 21 as in the case of stage I and wheels 23 are rotatably mounted on the axles 22, but such that they are freely mountable on and removable from the axles. The guide rails 24 are laid on the supporting floor 17 for supporting the stage II, said floor being elongated by 8 to meters extending beyond the original floor 17 in a direction different from the direction in which the crane for hoisting and lowering the stage III runs. Thus, the stage II can be moved on the rails horizontally to a waiting place provided on the extended floor 17.

During the usual furnace operating time the wheels 23 are removed in order to provide a tight joint between the upper mantle and the large bell. In this case the stages II and III are joined with each other by connecting the upper mantle 21 of the small bell and the large bell cup 2 by bolts or the like. Alternatively the wheels can be made of a structure provided with a resilient means, instead of removing the wheels for securing the tight joint between the upper mentle and the large bell. The wheels used for moving the stages I and II can be replaced by moving rollers.

The method of the present invention for replacing the large bell and large bell cup by using the abovementioned structure of the present invention will now be explained.

First of all, the stages I and II are horizontally moved aside in a direction at right angles to the direction the girder 9, extends as shown in FIG. 4, on the rails 20 and 24 laid on the elongated supporting floors l6 and 17 respectively to the waiting places provided on the respective floors, where the stages I and II may remain until the replacement work on the stage III is finished. To do this, it is necessary to jack up the entire stage II, after unbolting the joint between the stage II and the stage III, and to mount the wheels 23 on the axles 22 on the stage II so as to be able to move stage II horizontally on the guide rails 24, as stage I can be moved. Subsequently, only the stage III, that is, the large bell and large bell cup, is lowered down onto the ground or the operating floor 11 by means of the furnace top crane l0. Thereafter, a new or rebuilt stage III is hoisted up from the ground or the operating floor to the original position thereof in the furnace top.

Thereupon, the stages I and II waiting in the waiting places, as shown in FIGS. 5 an 6, are moved back to their original positions.

Thus, with the furnace top structure of the present invention the time and labor required for the replacement of the large bell 1 and large bell cup 2 can be greatly reduced, as is shown in FIG. 7b, because the stages I and II are simultaneously moved aside horizontally on the guide rails laid on the supporting floors, without the necessity of lowering them down onto the ground or the operating floor, as was heretofore the case. Moreover, the equipment cost and space can be greatly reduced, because the capacity of the overhead crane and the waiting area on the operating floor need only be sufficiently large to accommodate stage I.

Therefore, at the present time, even though blast furnaces have a tendency to become increasingly large in size and to use a higher pressure, the present invention has a great practical value.

What is claimed is:

1. The combination of a blast furnace top structure including a first stage composed of a large bell and a large bell cup and including at least one further stage composed of a chute and a hopper and a small bell, a small bell cup and a hopper; and a means for replacing said first stage, said means having a top crane running in one direction for hoisting and lowering at least said first stage; at least one floor supporting the said further stage, said floor extending laterally of said furnace top structure in a direction different from the one direction in which said top crane runs, guide rails on said floor, and wheels mounted on said further stage which run on said rails, whereby said further stage can be moved on said rails to enable replacement of the first stage without the necessity of removing and lowering said further stage to the ground and raising and replacing it when the first stage replacement has been completed.

2. The combination as claimed in claim I in which there is only a single further stage and in which there is only a single floor supporting said further stage.

3. The combination as claimed in claim 1 in which there are two further stages, the first further stage being composed of a chute and a hopper, and the second further stage being composed of a small bell, a small bell cup and a hopper, and in which there are two floors, one for each further stage and rails on each floor and wheels on each further stage which run on said rails. 

1. The combination of a blast furnace top structure including a first stage composed of a large bell and a large bell cup and including at least one further stage composed of a chute and a hopper and a small bell, a small bell cup and a hopper; and a means for replacing said first stage, said means having a top crane running in one direction for hoisting and lowering at least said first stage; at least one floor supporting the said further stage, said floor extending laterally of said furnace top structure in a direction different from the one direction in which said top crane runs, guide rails on said floor, and wheels mounted on said further stage which run on said rails, whereby said further stage can be moved on said rails to enable replacement of the first stage without the necessity of removing and lowering said further stage to the ground and raising and replacing it when the first stage replacement has been completed.
 2. The combination as claimed in claim 1 in which there is only a single further stage and in which there is only a single floor supporting said further stage.
 3. The combination as claimed in claim 1 in which there are two further stages, the first further stage being composed of a chute and a hopper, and the second further stage being composed of a small bell, a small bell cup and a hopper, and in which there are two floors, one for each further stage and rails on each floor and wheels on each further stage which run on said rails. 